The Supreme Court’s unanimous rejection of the idea that the devolved legislatures possess a veto over Brexit shouldn’t have come as a surprise to anybody.

Even if you believe they ought to have one, there is very clearly no provision in the constitution for it and it would have been grossly improper for the judiciary to invent one. Reserved powers are Westminster’s domain.

Why then did the Scottish Government decide to join the case at all? Aside perhaps from some small hope of a complete Hail Mary delivering Holyrood the power to block Brexit, the obvious answer must be the hope that rejection would provide another ‘outrage’ that would spur the Scottish public towards independence.

Nicola Sturgeon and her ministers have been leaning heavily on that device since the June vote, but neither the Scottish public nor the British Government have behaved as the SNP hoped and expected. Now the high profile and incessant way they’ve warned of another referendum mean that, as Scottish blogger Ian Smart puts it, “there is no good way out of this”.

If the SNP walk away, they’ll leave a lot of chips on the table – but if they go all in, they seem more likely than not to lose the lot. It’s an invidious position.

Which is why one’s eye is drawn to this story from today’s Scotsman, which suggests that Scotland might be “heading towards a snap election” over the Nationalist budget.

It strikes me as improbable that the SNP can’t find sufficient compromises to buy off their fellow separatists in the Green Party, at least. But what if an election on a matter unrelated to independence were actually the escape route Sturgeon is looking for?

She doesn’t have the constitutional power to call a referendum herself (and that matters), but it’s very likely that Westminster would grant one if Holyrood voted for it. A poll, especially one precipitated by an unrelated issue like the budget, would provide a convenient means to test the waters.

If the SNP pick up seats, that might put the frighteners on Theresa May (although I wouldn’t count on it). On the other hand, if the unionist parties make the rather small number of gains needed to wipe out the SNP/Green majority for independence in the Scottish Parliament, that would take a lot of pressure off the First Minister and give her base somebody else to blame for the delay.